Registry Repair

Hi Guys----Ok, I ran a registry repair tool and deleted all items it found that were deemed safe. Many other items I have to make the decision wheter or not to delete.
Using 1 registry error as an example, (Registry item "startup" references the missing file "programs"), how do I research this to determine what action to take if any.

 

Take a look at this site http://www.winguides.com/registry/registry-repair.php

 

Telecom69----Thanks for the response. That site is quite interesting but I can't find a solution to my question there. I suppose if I have 30 or 40 Registry errors I could backup the registry and delete an error, wait a day to see if it creates a problem and then repeat the process again and again.
I would still much rather research each problem and determine the course of action but I still don't have a clue as to how to accomplish this.